Fertility control methods must be effective and safe and should afford no more than a minimum of side-effects both in terms of frequency and intensity.
Based on present knowledge a contraceptive must satisfy the following requirements in order to afford the maximum guarantees from a medical and psychological-social standpoint:
(1) Pearl and mathematical index as close as possible to 0.
(2) Minimum production of side-effects and with the smallest possible frequency.
(3) Minimum damage to the gyneco-endocrinal system.
(4) Minimum medical contraindications.
(5) Low medical extraction index.
(6) Very low expulsion index.
(7) Very high index of continuity or permanency.
(8) Contraceptive effect which lasts for years.
(9) Ability to be fitted easily not only by medical personnel, but also by paramedical personnel in case of need, with minimum risk to the patient.
(10) No need for continual medical inspection.
(11) Return of fertily on removing the contraceptive.